Cold intermediate layer

In [48], it was shown that, in order to simulate the cold intermediate layer of the Black Sea (see [3]), one should take into account the dependence of the vertical turbulent mixing coefficient on the density stratification of the waters. In this case, the optimal coefficients in the well-known formula by Munk-Anderson for the Black Sea occurred to be an order of magnitude lower than those for the World Ocean. 

The absolute minimum of the water temperature in the Black Sea is usually encountered in the upper part of the main pycnocline and has values of 6.5-75 °C (see Fig. 3a). Only in severe winters is it located in the UML. The layer with a temperature lower than 8 °C is referred to as the cold intermediate layer (CIL) [2-4], In the warm period of the year, it is sandwiched between the seasonal and main pycnoclines of the Black Sea with a slight local decrease in the vertical density gradients (see Fig. 3a). Over the greater part of the area, at the end of the winter, the upper boundary of the CIL (the upper 8 °C isotherm) is exposed at the sea surface. At this time, the major part of the CIL is located inside the UML and only its lower part is related to the main pycnocline. Thus, in this period, the CIL provisionally becomes the cold surface layer. 

The T,S structure of the Black Sea waters consists of a few characteristic layers with different thicknesses top-down the upper mixed layer, the seasonal pycnocline (thermocline) the cold intermediate layer, the main pycnocline (halocline) the isothermal intermediate layer the thickest deep layer with a slow temperature and salinity increase with depth and the near-bottom mixed layer. 

Belokopytov V (1998) Long-term variability of cold intermediate layer renewal conditions in the Black Sea. In Ivanov LI, Oguz T (eds) Ecosystem modeling as a management tool for the Black Sea. Kluwer, Dordrecht, p 47... 

Ivanov LI, Besiktepe S, Ozsoy E (1997) The Black Sea cold intermediate layer. In Ozsoy E, Mikaelyan A (eds) Sensitivity to change Black Sea, Baltic Sea and Northern Sea. Kluwer, Dordrecht, p 251... 

Tuzhilkin VS, Nakolushkin IY (1999) Climatic features of the Black Sea cold intermediate layer ventilation. In International conference on oceanography of the eastern Mediterranean and Black Sea. Similarities and differences of two interconnected basins. 23-26 February 1999, Athens, Greece. Abstracts, p 175... 

Correlation Between Temperature of the Cold Intermediate Layer and SST 268... 

Krivosheya VG, Ovchinnikov IM, Skirta AY (2002) Intraannual variability of the cold intermediate layer of the Black Sea. In Zatsepin AG, Flint MV (eds) Complex investigation of the northeastern Black Sea. Nauka, Moscow, p 27 (in Russian)... 

The authors prove that the features of the hydrochemical structure of the sea are closely related to the hydrophysical factors and their variability, first of all, with the intensity of water exchange via the Bosphorus Strait, the Danube River runoff, and the temperature of the cold intermediate layer. The possi-... 

Observations over the position of the boundary of the hydrogen sulphide zone in the northeastern part of the Black Sea showed that its interannual variations are related to the wintertime temperature conditions and the formation of the balance between the riverine water supply, the delivery of saline waters via the Bosphorus, and the wintertime formation of the cold intermediate layer enriched in oxygen. 

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